Blender - Blender is the open source, cross platform suite of tools for 3D creation.
pixeldudesmaker - Simple, web-based pixel art character generator.
Sculptris - Sculptris: Enter a world of digital art without barriers.
Game Character Hub - helper program for game design (RPG Maker XP/VX and more)
Misfit Model 3D - Misfit Model 3D is a 3D model editor that basically operates with triangle-based models.
Sketchfab - Sketchfab is an industrial design software tool is useful for ideation and for beginners in the industrial design field.